Door-operating apparatus



E. H. GRIM. DOOR OPERATING APPARATUS.

APPLICATION FILED MAY 25. 192|.

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E. H. GRIM.

'DOOR OPERATING APPARATUS.

APPLICATION FILED MAY 25, 192|.

1,409,096.l Patented Mar. 7,1922.

4 SHEETS-SHEET Z.

x IFT d I i INI/ENTH MM III A TTORNEI'S mlm m E, H. GRIM.

DO0R OPERAT|NG APPARATUS. APPLlCATlO-N FLED MAY 25. 1921.

Patented Mar. ,7, 1922.

4 SHEETS-SHEET s.

A TT ORNE 78 GRIM.

DOOR OPERATING APPARATUS.

APPLICATION FILED MAY 25, 1921.v

Patented Mar. 7, 1922.

4 SHEETS- WITNESSES UNITED STATES EDWARD H. GRIM, YF DOTT, WEST VIRGINIA.

DOOR-OPERATING APPARATUS.

Application filed May 25,

To @ZZ ywhom t 77mg/ concern: Y

Ee it known that EDWARD Irl. GMM, a citizen ot the United States, and a resident of Dott, in the county of Mercer and State ot Vilest Virginia, have invented certain new and useful Improvements in Door-Operating A#"npparatus of which the following 1s a speciiication.

This invention relates to a door operating apparatus, and more particularly to an apparatus for opening and closinga door for forming a closure for the entrance of a mine or tunnel, and through which entrance railway cars pass.

rlhe object oi" the invention is to provide means by which the door will be automatically opened when car or train'` ot cars approaching the entrance of the mine has reached a predetermined distance from the door. j

it is also an object of the invention that upon the passage of the car or train of cars through the entrance of the mine that the door will be again automaticallyY closed.

lt is a further object of the invention that means be provided whereby an alarm will be continuously sounded while the door remains fully open.

A still 'further object of the invention is to provide mechanicalV means whereby the door'will be locked against closing during the passage oi the car or train of cars through the entrance oit the mine @ther objects and objects relating to details oi? construction. combination and arrangement ot parts will hereinafter appear in thedetailed description to follow.

, The invention is illustrated by. way of example in the accompanying drawings, in which: l

Figure 1 .is an' end elevation of a door forming the closure to a mine entrance as shown. and vlikewise illustrating the apparatus of the present invention associated with the door torV opening and closing the same, parts being shown in `section for more clearly illustrating the invention,

Figure 2 vis a top plan view oit' the saine,

Figure 3 a front elevation of the saine,

Figure 4 is a diagrammatic view illustrating the electrical connections for the apparatus utilized in the` present invention,

Figure 5 is a detail perspective view of the switch post, l Y Y Y 'Figure G is'an end elevation of the door stop tor holding the same against closing Specification of Letters Patent.

Patented Mar. 7, 1922.

1921. Serial N0. 472,609.

while the car or train of cars is paing through the entrance or doorway of the mine.

Referring to the drawings more particularly, si indicates generally a door which forms a closure to a mine penetrating the side of a hill or mountain as generally indicated at B. About the door there is constructed a frame structure as generally indicated at C which comprises the two side posts and the top cross member 11. The

door is suitably hinged to one of the side posts 10 by the means of hinges as indicated at l2. ln the present instance there extends into the mine a pair of railroad rails 13 and 14 which are suitably supported by the ties as shown, and said ties also insulating the rails from the road-bed, and the door A being hinged so that it may freely swing over the top of the rails as shown in Figures 1 and 3. The door is adapted to be swung ufpon its hinges in the position indicated by dotted lines in Figures 1 and 2, and at a point adjacent the free end of the door when swung to this position there iS suitably positioned and secured a motor casing` generally indicated at 15 in which there is housed an electric motor indicated at 16.

Upon one end of the motor shaft there is secured a driving pinion 17 which is adapted to mesh with the gear wheel 18 carried by the shaft 19, the shaft 19 being suitably journaled in a bearing 2O formed upon the top of the motor casing. To the forward end ol2 the shai'it 19 there is secured a drum 20, to which the one end of a cable 21 is connected. The cable otherwise passes over a pulley 22 positioned upon the forward wall 23 ot the motor housing 15 and from thence is extended and connected to the free` end of the door A at a point adjacent its lower end as indicated at 2t. Figures 3 and 4. As is obvious upon energizing the motor 16, the cable 21 will be drawn for opening thc door A.

Also upon the forward wall 23 ot' the motor housing 15 there is secured a housing 2G in which there is mounted a pair of electro-magnet coils 27 each of which is provided with a. central core as indicated at 2S, Figure and with which a plate 29 carried by the door A is adapted to engage and form an armature therefor when the door is in its open position as shown in Figure 2. )is is obvious by energizing the magnet coils 27 the door A would be held against movenient when the plate 29 carried thereby engages with the cores 28 of the magnets.

Upon the inner side of the post 10 to which the door A is hinged there is positioned a vertical guide-way30 which is adapted to slidingly accommodate a cylin-J drical shaped weight 31. To the upperend of the weight 31 there is connected a cable 32 and encircling this cable is a coil spring 33 having its lower end seated upon the upper end of the weight 31. Adjacent the top of the guide-way 30 there is formed a partition 34 having a central opening through which the cable 32 may pass and adapted to form a stop for the spring 33 when the weight 31 is moved to such a position; Above the partition 34 there is journaled transversely of theguide-way apulley 35 Vover whichthe cable 32 passes, said cable `having its other end connected to the free end 36 of a bracket 37, and said bracket be- ,ingsecured to the inner side of the door A.

at the upper end thereof and adjacent the hinged en-d of the door as shown in dotted lines in Figure 2.' The portion of the bracket which extends from the door is substantially L-shaped as shown in dotted lines in Figure 2, and is adapted to litt the weight 31 when the door is swung to its open posiv'tion and upon the release of the door to permit the same to be swung to itsrclosed posi- `tion by the pull exerted by the weight 31.

.The piirpose of the spring will later be explained.

. Forward to the motor housing 15 and substantially iny alinement with the magnet coils 27 there is positioned a post 38. irdjacent the upper end ot the post 38 and from the rear side'thereot, there extends a support 39 at substantially right angles to the post. N ear the outer end o1 this support there is secured or positioned a downwardly extending pin 40, said pin having pivoted on its lower end an elongated member 41 which has an enlargement 41 'formed on its outer end, and said enlargement being provided Vwith a slot 42. An extension arm 42 has its` inner end secured to the member' 41 by the means of a bolt 43, the bolt extending vthrough the slot 42 and adapted to permit-v the arm 42 to be moved inward or outward on its outer end swung upon the bolt 43 as a pivot. The bolt 43 is ot course provided with a nut, not shown, by which theI arm may be secured in the position desired. Upon the forward end of the member 41 there is secured an extension member 43 having an enlarged portion at its 'free end as shown, and being disposed between a pair of L-shaped clips 44 and 44 which are secured to the rear side face of the post 38. As is obvious by swinging movement of the arm 42 the member 43 may be brought into engagement with either of the clips 44 or 44.v ,Also there is provided acoil spring 45 which' encircles'the pin 40, as shown and having its one end secured to the support 39, while its other end. is suitably secured to the member 41, and the spring being adapted to yieldingly hold the member 43 in engage-Y ment with the clip 44 asshown in Figure 5. Also upon the outer side of the post 38 there may be secured a shield 46 which is adapted to extend substantially the same distance as the support 39.

Also there is secured to the post 38 to the iront side thereof a resilient strip 47 by the means of a screw bolt as indicated at 48. A U-shaped member 49 is also secured to the post and adapted to limit the outward movement of the free portion of the strip 47.

Upon' the rear lside of the posty there is secured astrip 50 with which there is formed `for positively holding thedoor `in its openV position which, referring to Figures 2 and 6, comprises a .rocker arm 53 which is carried by a shaft 54, said shaft being journaled in a pair of bearings 55 and said. bearings being supported by the ends of a pair of extended ties 5G, as shown. The outer end oi' the rocker arm 53 is formed with ank upwardly extending portion 57 while its inner end comprises a pair of' diverging arms 58- which'extend upwardly and then forwardly,

soV

as shown. Upon the forward, end portions of the arms 58 there is secured Va strip 59 which normally is positioned adjacent the outer side of the rail 14.

r1`he strip 59 is supported in a raised position with respect to the ties of the railroad track by the means of a pair or" posts 60, a post being located adjacent each end of the Vstrip and each post being secured to an associated tie, said posts each having encircled tliereabout acoil spring 61 which normally press the strip 59 .againstV the heads 62 formed upon the upper end ot each post; V\.7hen a car passes Voverthe rails-13 and 14 the flanges ot the wheels associated with said car will of course likewise pass over the inner edge of the strip-59 Yand thus will `force the same downwardly against the tension ofV the spring-S51 and cause the outerV end of the rocker arm 53 to move upwardly. 1n case that the door is closed as shown in dotted lines in Figure 2, the upwardlyv extending portion 59 of the rocker arm will be disposed upon the inner side of the door and Y `,thus positivelyV lock the samelfrom closing.

This action of the rocker arm will of course only continue while the car is passing over the strip 59 or in other words, while a car is passing through the entrance to the mine Referring to Figure 4, 64 indicates a battery which is grounded upon its negative side as indicated at 63 and its positive side connected with a feed wire indicated at 65. From the feed wire 65 there extends a wire 66 which is connected at its other end with the switch member 43, Figure 5. Also there extends from the feed wire 65 a wire 67 which connectswith the coils 27, said coils being in series, and from the coils there is extended a` wirev68 which is suitably connected to the inner rail'14. From the L-shaped clip 44 upon the post 38 there extends a wire 69 whichconnects at itsrother end with one terminal post of the motor 16, and the other terminal of the motor being connected to a wire 70 which in turn is connected at its other end with the rail 14. The other clip 44 carried upon the post 38 is connected through a wire 71 which-in turn connects with a wire 72, the wire 72 having connected at each ot Vits ends the one terminal post ot a. bell 73, the other terminal-post of each bell 73 being connected to the rail 14 bythe means of a wire 74 as shown. The rail14 has suitable insulation interposed in its length at the points 75 while the rail 13 is grounded, as indicated at 76.

1n the operation of the present device, assuming that Athe door is closed and likewise that the switch member 43 is in contact with the clip 44, as shown in detail in Figure 5,- and that a` car is coming from the mine and that said car has reached a position so that one of its wheels is disposed upon the insulated rail 14. lVhen this occurs the axle and wheels of the car will form a path to the ground from the rail 14 and simultaneously therewith, current will tiow through the wire 66 and switch member 43 from thence through the wire 69 through the motor 16 and to the rail 14. Y The rail 14 being grounded the current will of course return to the grounded side ot the battery 63. This will energize the motor 16 and cause the cable 21 to be wound upon the drum 2O for opening the door A. Also at this time current will flow through the wires 67, coils 27 and the wires 68 to the rail 14, and from thence to the ground, and returned to the battery, thus energizing the coils 27 and so when the door A has fully reached its open position the plate member Q9 carried thereby will be magnetically held and in turn holding the door against closing. Previous to the time when the plate 29 engages with t-he magnet cores 28 the free end ot the door will engage with the resilient strip 47, and therefore the impact ot the door against the magnet will be lessened. Alec at this time the weight'31 will be lifted and the spring 33 engaged with the partition 34 and likewise cause a lessening otl the force with which the door may strike the magnet cores 28. Likewise when the door is fully open the free end thereof will engage the arm 42 and swing the member 43 out ot contact with the clip 44 and in contact with the clip 44', whereupon the current will be cut off from the motor 16, and the current will at the same time energize the bells 7 3, said current flowing from the switch member 43 through the wires 71 and from thence through the wires 72 to one terminal of the bells 43 and from the other terminal of the bells43 through the wires 74 to the rail 14, which as before stated, is grounded.

The bells of course will continue to ring as long as the cars are passing over the insulated portion ot the rail 14, and thus continuously sounding the alarm to signal that the door is open. Also as the train is passing through the door-way the rocker arml 53 is actuated in the manner hereto- :tore described, and the door locked in its open position.

After the cars have passed through the entrance to the mine and the wheels thereof no longer traveling over the insulated portion of the rail 14, the current 'will simuln taneously cease. flowing through the coils 27 and thus no longer holding` the door against closing. The weight 31 will then draw the door to its closed position and at the same time the arm extension 4i., Figure 5, will be permitted to return to its normal position, that is, so that the member will again engage with the clip 44. The rocker arm 53 will of course have assumed its normal position immediately upon the train passing thereover and therefore will not interfere with the closing of the door. Likewise with the arm 42 assuming its original. position, the bells 73 will cease to ring.

In case a car is coming in the opposite direction, that is, in the direction to pass into the mine, the same operation of the apparatus heretofore described for opening and closing the door when a car is coming Ytrom the mine will be repeated. and therefore no detailed description thereof will be made.

I claim- 1. In combination, a hinged door adapted to for a closure for an entrance to mine. through which a railway track passes. means for insulating one ot the rails forli ing the railway a predetermined distance beyond. each side of the door. an electric motor positioned at one side. of the railway traclr and within the path of said door when brought to an open position`A a drum driven by said motor, a cable extending between said drum and the treo end ot the. door adapted to draw the door open when said motor is energized, a source of electric current supply, a circuit for said electric motor including said insulated' rail and source of current supply which will be closed when a car comes upon Asaid insulated rail.

2. 1n combination, a hinge door adapted to form a closure for an entrance toa mine through which a railway track passes, means for insulating one ot the rails forming the railway a predetermined distance beyond each side oi' the door, an electric motor positioned at one side ot the railway track and within the path oi said door when brought to an open position, a drum driven by said motor, a cable extending between said drum and the iree end ot the door adapted to draw the door open when said motor is energized, a source of electric curient supply, a circuit for said electric motor including said insulated rail and source of current supply and mechanical means adapted to be actuated by a car upon the railway track for positively holding the door in its open position during the time that a caris passing through said door.

3. In combination, a. hinged door adapted to form a closure for an entrance to a mine through which a railway track passes, means for insulating one 'of the rails 'torming the railway a predetermined distance beyond each side ot the door, an electric motor positioned at one side ot the railway track and within the path of said door when brought to an open position, a drum driven by said motor, a cable extending between said drum and the free end of the door adapted to draw the door open when said motor is energized, a source of electric current supply, a circuit for said electric motor including said insulated rail and source oi current supply, a rocker bar mounted adjacent the rail disposedv nearest the motor and said rocker bar extending transversely ofthe railway track and adapted to have its inner end depressed by a car wheel passl through ing over the adjacent rail. and means associated with the other end voit said rocker arm adapted to engage the door for holding the same in its open Vposition-` 4L. In combination, a hinged door adapted to form a closure for an entrance to' a mine which la railway track passes, meansfor insulating one of the rails forming'theV railway a predetermined distance beyondl each side of the door, an electric motor positioned at one sidevot the railway track and within the path of said door when brought to an open position, a drum driven by said motor, a cable extendnig between said drum and the tree end of the door adapted to draw the door open when said motor is energized, a source of electric current supply, a circuit for saidelectric motor including said insulated rail and Y :ifioaoee source ot current supply,` a rocker bar mounted adjacent the rail 'disposed nearest the motor and said rocker bar extending' transversely of the railway track and adapts ed to have its inner enddepressed by a car wheel passing over the adjacent rail', anda projection, extending upwardly from the otherend ot the rocker arm adaptedtobe brought in iront oi' the door for holding the saine in its open position when the inner end or said rocker arm is depressed by the passage ot a railway car.

5. ln combination, a hinged door adapted to form a closure `for an entrance to a mine through which a railway track passes, means tor insulating one of the rails forming the railway a .predetermined distance beyond each side of the door, an electric motor positioned at one side oit the railway track and within the path of said vdoorwhen brought to an open position, a drum driven by said motor, a cable extending between said drum and the free end oi the door adapted todraw the door open when said motor is energized, a source ot electric currentsupply, 'a circuit for said electric motor including vsaid insulated rail, a rocker bar mounted adjacent the rail disposed nearest the motor .and said rockerV bar extending transversely of the railway track and adapted to have its inner end depressed by a car wheelpassing over the adjacent rail, a projection extending up wardly from the other end of the'rocker arm adapted to be brought in front ofthe door for holding the same in its open position when the inner end of said rocker arm is depressed by the passage of a railway car.

6. in combination, a hinged door adapted to form a closure for an entrance to a mine through which a railway track passes, means tor insulating one oi the rails of the railway tr-l ck a predetermined distanceY beyond each side of the door, an electric motor positioned one side ot the railway track-'and within the path of said door, cable meansl extending from said motor whereby 'when the same is energized the door will be open, a housing for said motor and anelectro'fmagnet carried by said housing, an armature carried by said door adapted to engage said electro-magnet Vwhen the door is brought to its openvposi-V tion, a source oi electric current supply, an electric circuit for said motor, including the insulating rail and sourceV of current supply adapted to be closed when a ear is disposed upon said insulated rail, means Jfor opening said motor circuit, when the door has reached its open position and an electric cir. cuit for said electromagnets adapted to be closed when a car is disposed upon said insulated rail. v

7. lnl combination, a hinged door adapted to form a closure for an entrance to a mine through which a railway track passes, means for insulatingone of the rails forming the railway a predetermined distance beyond each side of the door, an electric motor positioned at one side of the railway t-rack and within the path of said door when brought to an open position, a drum driven by said motor, a cable extending between said drum and the free end of the door adapted to draw the door open when said inotor is energized, a source of electric current supply, a circuit for said electric motor including said insulated rail and source of current supply which will be closed when a car comes upon said insulated rail, a post forward to said motor, and ineans carried by said post adapted to yieldingly bring the door to a stop when swinging to its open position.

8. In combination, a hinged door adapted to form a closure for an entrance to a mine through which a railway track passes, means for insulating one `of the rails forming the railway a. predetermined distance beyond each side of the door, an electric motor positioned at one side of the railway track and within the path of said door when brought to an open position, a drum driven by said motor, a cable extending between said drum and the free end of the door adapted to draw the door open when said motor is energized, a source of electric current supply, a circuit for said electric motor including said insulated rail and source of current supply which will be closed when a car comes upon said insulated rail, apost forward to said motor, and a spring metal arm extending rearwardly from said post and adapted to yieldingly bring said door to a stop when swinging to its open position.

9. In combination, a hinged door adapted to form a closure for'an entrance to a mine through which a railway track passes, means for insulating one of the rails forming the railway a predetermined distance beyond each side of the door, an electric motor positioned at one side of the railway track and within the path-of said door when brought to an open position, a drum driven by said motor, a cable extending between said'drum and the free end of the door adapted to draw the door open when said motor is energized,

a source of electric current supply, a circuit forA said electric motor including said insulated rail and source of current supply which will be closed when a car comes upon said insulated rail, a post forward to said motor, a spring metal arm extending rearwardly from said post and adapted to yieldingly bring said door to a stop when swinging to its open position, and means whereby the position of said arm may be adjusted with respectto the time of engaging the door.

10. In combination, a hinged door adapted to form aclosure for an entrance to a mine through which a-railwa-y track passes, means for 'insulating ,one .0i the rails forming the railway a predetermined distance beyond each side of the door, an electric motor positioned at one side of the railway trackv and within the path of said door when brought to au open positioina di'umidriven Aby said niotor, a cable extending between said drum and the free end of the door adapted to draw the door open when said motor is energized, a source of electric current supply, a circuit for said electric motor including said insulated rail and source of current supply which will be closed when a car comes `upon said insulated rail, a post positioned forward to the motor, an arm extending at right angles from said post and its inner end being pivoted to the post and itsouter end adapted to be engaged by the door previous to reaching its open position, and means associated with the inner end of the arm adapted to open said motor circuit when the door has fully reached its open position.

ll. In combination, a hinged `door adapted to form a closure to a mine entrance through which a railway track passes, means for insulating one of the rails forming the railway a predetermined distance beyond each side of the door, an electric motor positioned at one side of the railway and within the path of said door when brought to its open position, a cable extending'between said motor and the free end of the door whereby said door will be opened when said motor is energized, a housing for said motor and an electro-magnet carried by said housing, an

armature carried by the free end of said door adapted to engage with said electro-magnet when the door is brought to its open position, a source of electric current supply, a circuit for said motor including the source of electric current supply and the insulated rail adapted to be closed when a car is brought upon said insulated rail, .a post forward to said motor, an arm extending from said post, the outer end of which is adapted to swing inwardly when engaged by the door, means associated with said arm whereby upon the door becoming fully opened, the motor circuit will be opened and a circuit for energizing the electro-magnet adapted to be closed when a car is present upon the insulated rail.

12. In combination a hinged door adapted to form a closure for an entrance through which a railway track passes, `means for insulating one of the rails forming the railway a predetermined distance beyond each side of the door, an electric motor positioned at one side of the railway track and within the path of said door when brought to its open position, means between said motor and door adapted to draw the door to its open position when said motor is energized, a source of electric current supply, a circuit for `said electric motor including said insulated rail and source of electric current supply, andV ioo door in its open position during the time a Vcar is passing through said door.

13. In combination a hinged door adapted to form a closure for an entrance through which a railway track passes, means for insulating one of the rails from the railway a predetermined distance beyond each side of the door, an electric motor positioned at one side of the railway track and within the path ka U-shaped bar pivoted at a point intermediate the ends of its bridge portion and having its one end disposed so that the same may be depressed by the passage of a railroad car thereoverfor bringing its other end into position for locking the door in its open position.

15. A device for holding bpen a hinged door forming the closure for an entrance through which a railroad passes during the passage of a car or train of cars therethrough, comprising a pivoted bar extending transversely of the rails of said track and having its one end disposed so that the same may be depressed by thepassage of a railroad'car thereover and bringing its other end into position for locking the door in its open position.

16. A device for holding open a hinged door forming the closure for an entrance through which arailroad passes during the passage of a car or train of cars therethrough, comprising a pivoted bar extending transversely of the rails ot said track and having its one-end disposed so that the same may be depressed by the passage oi' a railroad car thereover and bringing itsother end` into position for locking the door in its open position, and means associated with the bar adapted to hold the same in its non locking position.

17. In combination, a door adapted to form a closure for an entrance through which a railroadv track passes, said door being hinged to one side wall oithe entrance.

Yan electric motor positioned at the side of the railway track toward which the door swings for opening, means between said motor and the door adapted to draw the door openv when said motor is energized,acircuit lfor-said motor including a source of electric current supply, and means whereby said circuit will be closed "a suiiicient interval to open the door when a car isdisposed on said track a predetermined distance on either side of the door. f

18. In combination, a door adapted to form a closure for an entrance through which a railroad track passes, said door being hinged to one side wall ci the entrance, an electric mot-or positioned at the side ot the railway track toward `which the door swings for opening. means between said motor and the dooradapted te draw the door open when said motor is energized, a circuit ici' said motor including a source oielectric current supply, means whereby said circuit will be closed a sufficient interval to open the door when a car is disposed on said track a predetermined distance on either side oit the door, and means for opening the circuit when the door is fully opened.

19. In combination, a` door adapted to form a closure for an entrance through which a railroad track passes, said door being hinged to one side wall of the entrance, an electric motor positioned at the side of the railway track toward. which the door swings ior opening, means between said motor and the door adapted to draw the door ope-n when said motor is energized, a circuit ior said motor including a source of electric current supply, means whereby said circuit will be closed a suilicientinterval to open the door when a. car is disposed on said track a predetermined distance on Veither' side ot' the, door', and means for bringing the door to a stop upon the same reaching its fully open position.

20. In combination, a door adapted to 'form a closure 'for an entrance through which a railroad track passes, said door being` hinged to one side wall of the entrance, l

an electric motor positioned Vat the side of the railway `track toward which the door swings for opening, means between said motor and Vthe door adapted to draw the door open when said motor is energized, a circuit for said motor including a source of electric current supply, means whereby said circuit will be closed a sufficient interval to open the door when a car is disposed on said the railway track toward whichY the door Y swings. for opening, means between said motor and the door adapted to* dra-w the 'door open whensaid Vmotor is energized, a circuit for'said motor includingga source of electric current supply, means whereby said circuit will berclosed a suiiicient'interval to eoL open the door when a car is disposed on said track a predeterminedL distance on either side ot the door, an electro-magnet positioned in the path of said door and adapted lto engage the saine when iully open, an armature carried by said door, and means for causing said electromagnet to be energized when the door has reached its open position whereby the same will be retained during the passage of a railroad carv through the entrance.

ln combination, a door adapted to form a closure for an entrance through which a railroad track passes, said door being` hinged to one side wall of the entrance` an electric motor positioned at the side of the railway track to Yard which the door swings for opening, means between said motor and the door adapted to draw the door open when said motor is energized, a circuit for said motor including a source of electric current supply, means whereby said circuit will be closed a sufficient interval to open the door when a car is disposed on said track a predetermined distance on either side of the doorn an elcctromagnet positioned in the path oi' said door and adapted to engage the same when fully open, an armature carried by said door, means for causing said electromagnet to be energized when the door has reached its open position whereby the same will be retained during the passage of a railroad car through the entrance, and means for opening the circuit controlling said magnet upon the railroad car reaching a predetermined distance beyond either side of the door.

QSL In combination, a door adapted to form a closure for an entrance throughwhich a railway track passes, said door being hinged to one side wall of the entrance, an electric motor positioned at the side of the track toward which the door swings for opening, means between the motor and door adapted to draw the door open vwhen said motor is energized, a circuit for said motor including a source of electric current supply, means for closing a circuit when a car is disposed upon a track a predetermined distance beyond each side of the door, a post forward to the motor, and a switch carried by said post adapted to be disposed in the path of said door and operating thereby when said door is swung to its open position for opening the circuit of said motor.

24e. In combination, a hinged door adapted to form a closure for an entrance through which a railway track passes, an electric motor positioned at one side of the track, means between the motor and door adapted to draw the door open when said motor is energized, a circuit for said motor including a source of electric current supplv, means for closing a circuit when a car is disposed upon a track a predetermined distance beyond each side of the door, a post forward to the motor, a switch carried by said post adapted to be disposed in the path of said door and operated thereby when said door is swung to its open position 'for opening the circuit of said motor, and means associated with said switch whereby when the saine is operated for opening the motor circuit a circuit will be established or closed for operating a signal during the passage of a railway car through said entrance.

25. In combination, a door adapted to form a closure for an entrance through which a railway track passes, said door being hinged to one side wall of the entrance, an electric motor positioned at the side of the track toward which the door swings for opening, meansbetween the motor and door adapted to draw the door open when said motor is energized, a circuit for said motor including a source of electric current supply, means for closing the circuit when a car is disposed upon said track a predeter mined distance beyond each side of the door, a post forward to the motor, a pivoted arm extending from the post adapted to be engaged by the door when reaching its open position and swung in a predetermined direction, and means whereby with the swinging movement of said arm the circuit of said motor will be opened.

26. In combination, a hinged door adapted to form a closure for an entrance through which a railway track passes, an electric motor positioned at one side of the track, means between the motor and door adapted to draw the door open when said motor is energized, a circuit for said motor including a source of electric current supply, means for closing the circuit when a ca'r is disposed upon said track a predetermined distance beyond each side of the door, a post forward to the motor, a pivoted arm extending'from the post adapted to be engaged by the door when reaching its open position and swung in a predetermined direction, means whereby with the swinging movement of said arm i the circuit of said motor will be opened, and means also adapted to be operated by the swinging movement of said arm whereby a circuit will be closed for operating an alarm during the passage of a car through said entrance.

EDWARD H. GRIM. 

